accesses versus sequential accesses, a (very crude) estimate of the
effects of caching on random page accesses, and cost to evaluate WHERE-
clause expressions. Export critical parameters for this model as SET
variables. Also, create SET variables for the planner's enable flags
(enable_seqscan, enable_indexscan, etc) so that these can be controlled
more conveniently than via PGOPTIONS.
Planner now estimates both startup cost (cost before retrieving
first tuple) and total cost of each path, so it can optimize queries
with LIMIT on a reasonable basis by interpolating between these costs.
Same facility is a win for EXISTS(...) subqueries and some other cases.
Redesign pathkey representation to achieve a major speedup in planning
(I saw as much as 5X on a 10-way join); also minor changes in planner
to reduce memory consumption by recycling discarded Path nodes and
not constructing unnecessary lists.
Minor cleanups to display more-plausible costs in some cases in
EXPLAIN output.
Initdb forced by change in interface to index cost estimation
functions.
Initdb help correction
Changed end/abort to commit/rollback and changed related notices
Commented out way old printing functions in libpq
Fixed a typo in alter table / alter column
have the rl_completion_append_character variable. The tab completion
behavior doesn't seem to be quite perfect in that situation, but it's
better than failing to build at all...
rate
it's better than what used to be there.
* Does proper SQL "host variable" substitution as pointed out by Andreas
Zeugwetter (thanks): select * from :foo; Also some changes in how ':'
and ';' are treated (escape with \ to send to backend). This does
_not_
affect the '::' cast operator, but perhaps others that contain : or ;
(but there are none right now).
* To show description with a <something> listing, append '?' to command
name, e.g., \df?. This seemed to be the convenient and logical
solution.
Or append a '+' to see more useless information, e.g., \df+.
* Fixed fflush()'ing bug pointed out by Jan during the regression test
discussion.
* Added LastOid variable. This ought to take care of TODO item "Add a
function to return the last inserted oid, for use in psql scripts"
(under CLIENTS)
E.g.,
insert into foo values(...);
insert into bar values(..., :LastOid);
\echo $LastOid
* \d command shows constraints, rules, and triggers defined on the table
(in addition to indices)
* Various fixes, optimizations, corrections
* Documentation update as well
Note: This now requires snprintf(), which, if necessary, is taken from
src/backend/port. This is certainly a little weird, but it should
suffice
until a source tree cleanup is done.
Enjoy.
--
Peter Eisentraut Sernanders väg 10:115